When running tests, installing operating systems, and compiling software for my Ultra 5, I came to the stunning realization that hey, this system is 64-bit, and all of the operating systems I installed on this Ultra 5 (can) run in 64-bit mode.

"Besides, in this day and age, you should almost never micro-optimize your code for a specific CPU architecture. Unless you are comfortable holding all the details of a 20-stage pipeline, different latencies for dozens of instructions, complex branch prediction, and the state of 128 rename registers in your head at once, the compiler will do a better job than you. And all your micro-optimizations will be useless when the next Intel chip comes out with different performance characteristics."

Do you really belive that compilers model processors to that detail? They don't. There is no need to do that (and is in reality impossible) to get good performance out of the processor, and that applies for human coders also.